Files
linux/drivers/gpu/drm/omapdrm/displays/encoder-tfp410.c
Laurent Pinchart 3f3623dd0f drm/omap: Remove enable checks from display .enable() and .remove()
The displays (connectors, panels and encoders) bail out from their
.enable() and .disable() handlers if the dss device is already enabled
or disabled. Those safety checks are not needed when the functions are
called through the omapdss_device_ops, as the .enable() and .disable()
handlers are called from the DRM atomic helpers that already guarantee
that no double enabling or disabling can occur.

However, the handlers are also called directly from the .remove()
handler. While this shouldn't be needed either as the modules can't be
removed as long as the device is in use, it's still a good practice to
disable the device explicitly. There is currently a safety check in
.remove() in some drivers but not all of them.

Remove the safety checks from the .enable() and .disable() handlers, and
add missing ones in the .remove() handler.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2019-03-18 11:42:11 +02:00

158 lines
3.8 KiB
C

/*
* TFP410 DPI-to-DVI encoder driver
*
* Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
* Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "../dss/omapdss.h"
struct panel_drv_data {
struct omap_dss_device dssdev;
struct gpio_desc *pd_gpio;
};
#define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)
static int tfp410_connect(struct omap_dss_device *src,
struct omap_dss_device *dst)
{
return omapdss_device_connect(dst->dss, dst, dst->next);
}
static void tfp410_disconnect(struct omap_dss_device *src,
struct omap_dss_device *dst)
{
omapdss_device_disconnect(dst, dst->next);
}
static int tfp410_enable(struct omap_dss_device *dssdev)
{
struct panel_drv_data *ddata = to_panel_data(dssdev);
struct omap_dss_device *src = dssdev->src;
int r;
r = src->ops->enable(src);
if (r)
return r;
if (ddata->pd_gpio)
gpiod_set_value_cansleep(ddata->pd_gpio, 0);
dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
return 0;
}
static void tfp410_disable(struct omap_dss_device *dssdev)
{
struct panel_drv_data *ddata = to_panel_data(dssdev);
struct omap_dss_device *src = dssdev->src;
if (ddata->pd_gpio)
gpiod_set_value_cansleep(ddata->pd_gpio, 0);
src->ops->disable(src);
dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
}
static const struct omap_dss_device_ops tfp410_ops = {
.connect = tfp410_connect,
.disconnect = tfp410_disconnect,
.enable = tfp410_enable,
.disable = tfp410_disable,
};
static int tfp410_probe(struct platform_device *pdev)
{
struct panel_drv_data *ddata;
struct omap_dss_device *dssdev;
struct gpio_desc *gpio;
ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
if (!ddata)
return -ENOMEM;
platform_set_drvdata(pdev, ddata);
/* Powerdown GPIO */
gpio = devm_gpiod_get_optional(&pdev->dev, "powerdown", GPIOD_OUT_HIGH);
if (IS_ERR(gpio)) {
dev_err(&pdev->dev, "failed to parse powerdown gpio\n");
return PTR_ERR(gpio);
}
ddata->pd_gpio = gpio;
dssdev = &ddata->dssdev;
dssdev->ops = &tfp410_ops;
dssdev->dev = &pdev->dev;
dssdev->type = OMAP_DISPLAY_TYPE_DPI;
dssdev->output_type = OMAP_DISPLAY_TYPE_DVI;
dssdev->owner = THIS_MODULE;
dssdev->of_ports = BIT(1) | BIT(0);
dssdev->bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_SYNC_POSEDGE
| DRM_BUS_FLAG_PIXDATA_POSEDGE;
dssdev->next = omapdss_of_find_connected_device(pdev->dev.of_node, 1);
if (IS_ERR(dssdev->next)) {
if (PTR_ERR(dssdev->next) != -EPROBE_DEFER)
dev_err(&pdev->dev, "failed to find video sink\n");
return PTR_ERR(dssdev->next);
}
omapdss_device_register(dssdev);
return 0;
}
static int __exit tfp410_remove(struct platform_device *pdev)
{
struct panel_drv_data *ddata = platform_get_drvdata(pdev);
struct omap_dss_device *dssdev = &ddata->dssdev;
if (dssdev->next)
omapdss_device_put(dssdev->next);
omapdss_device_unregister(&ddata->dssdev);
WARN_ON(omapdss_device_is_enabled(dssdev));
if (omapdss_device_is_enabled(dssdev))
tfp410_disable(dssdev);
return 0;
}
static const struct of_device_id tfp410_of_match[] = {
{ .compatible = "omapdss,ti,tfp410", },
{},
};
MODULE_DEVICE_TABLE(of, tfp410_of_match);
static struct platform_driver tfp410_driver = {
.probe = tfp410_probe,
.remove = __exit_p(tfp410_remove),
.driver = {
.name = "tfp410",
.of_match_table = tfp410_of_match,
.suppress_bind_attrs = true,
},
};
module_platform_driver(tfp410_driver);
MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
MODULE_DESCRIPTION("TFP410 DPI to DVI encoder driver");
MODULE_LICENSE("GPL");